Based on the pressure-state-response(PSR)model and the policy of co-governance of five water categories, we constructed an evaluation index system and used the analytic hierarchy process(AHP)method to examine and assess the water environmental security in Zhejiang Province. In the PSR evaluation index system, the water pollution control index has the largest weight, and the indices of discharge loads of the major pollutants, the proportion of GDP of high water-consuming industries, and the rate of industrial wastewater discharge standards have relatively large weights, indicating that the typical industrial economic activities are the threats to the water environmental security. The response index increases to the largest extent, and the pressure and state indices show stable fluctuations. These are favorable results from positive measures taken by the related government departments with the development of the industrial economy. With the rapid development of the economy, reducing the discharge loads of the major pollutants, reducing the proportion of GDP of high water-consuming industries, improving the rate of industrial wastewater discharge standards, and increasing investment in environmental protection are key factors in the improvement of water environmental security. It is suggested that, with the co-governance of five water categories, we should speed up the adjustment and upgrade of industrial structure, reduce industrial water consumption, increase investment in environmental protection, improve the water environment, and ensure water supply capability, in order to promote the healthy development of the water environment system for Zhejiang Province.